Motor-control system.



J. H. HALL.

' MOTOR- CONTROL SYSTEM.

APPLIOATIONIILED SEPT. 5, 1913..

1,122,744. Patented Dec. 2 1914.

WITNESSES: INVENTOR (SM yd I I gf, i:.03w&-

ATTORN EY 25 A further object of my invention is to of the switch S the contacts of the switch so 1,122,744. Specification of Letters Patent. Patented De 29 1914,

' Application filed September 5, 1913. Serial No. 788,280.

171) allwhom it may concern: iS ShOWII at M in Fig. l, and-at N in Be it known that I, JAY H. HALL, a citi- Fig. 2. zen. of the United States, residing at (Jleve- Referring now to Fig. 1, the operation of land, in the county of Cuyahoga and State the control system is as follows: When the 5 of Ohio, have invented new and useful Imoperator moves th switch M to position 1, provements in. Motor-Control Systems, of the motor circuit is closed, including the which the following is a specification. resistances R, R, and R and the winding y invention relates to motor-control sys C of the switch S. This circuit may be terns, particularly to systems in which the traced as follows: from the positive through control of an electric motor is effected par-' the series field F, the contact finger 5, the 5 tially by a manually operated controller and controller contacts, the contact finger 6, the partially by automatic means. motor armature A, the contact finger 7, the More particularly, it relates to such a syscontroller contacts, the contact finger 8, the tem in which magnetically operated resistance R,the switch winding C, and switches are used for removing the resistthe resistances R and R to the negative. ance from the motor circuit controlling the If t e motor current exceeds a predeteracceleration of the motor. mined value, the switch S will. remain open One of the objects of my invention is to and when the current is reduced due to the maintain at wil the maximum resistance in speeding up of the motor, the switch will 20- the motor circuit and o set in operation the close but will not cause any of the resistance successive closure of a series of magnetito be cut out. When the operatormoves his sally-operated switches for automatically switch to position 2, the motor circuit goes removing the resistance from the motor cirfrom the contact finger 7 to the contact finger 9, and thence through the winding C enable the operator to open the switches, and the winding C and the resistances R insert the resistance inv the motor circuit at and R to the negative. The resistance R is a time when no current goes through their cut out, causing the current of the motor contacts, thus preventing the formation of circuit to increase, and if the current ex- 30 serious arcing at the switch contacts. ceeds the value at which the switch S is adther objects and advantages of my inusted to operate, it will remain open until vention will be hereinafter described. the motor current has diminished, where- In the accompanying sheet of drawings, upon it will close its contacts. The current Figure l is ardiagrammatic' representation no longer flows through the contacts of the 35 of a motor control system embodying my switch S and its winding C, but goes invention. Fig. 2 is a modification showing through the contacts of the switch S the another form which my invention may aswinding C and the resistance R to the sume. negative. Since the winding C is now de- Referring to the drawings, the motor to energized the switch S will drop open.

40 be controlled is shown with the armature A --The switch S will remain open, if the motor and the series field winding F. The resistcurrent exceeds the value at which this ances for 00 trolling the motor circuit are switch is adjusted to operate, until the curindicated at R and R The resistances rent has diminished, whereupon the switch are'arranged to be automatically controlled will close, thereby cutting out the resistance 5 by means of the switches S, S and S these R The motor circuit will then be as folswitches having operating windings C, lows: from the positive through the series and C arranged to be connected in the field F, the contact finger 5, the controller motor circuit I prefer to use for these contacts, the contact finger 6, the motor switches the type of switch disclosed in armature A, the contact finger 7, the con- 50 Eastwoods Patent, No. 1,040,292, which has trolle-r contacts, the contact finger 9, the 1 the peculiar characteristic of remaining winding C the contacts of the switch S open when the current in its operating the winding C and the contacts of the winding exceeds a certain value, and operswitch S to the negative. All of the startates to close the switch contacts when the ing resistance has been cut out and the mo- 5 -current is reduced. The operators switch tor operates at its normal speed. 10

If the operator wishes to reduce the speed of the motor, he can move the switch LI to position 1 thereupon cutting off the current through the windings and the contacts of the switches S and S and inserting the resistances R, RZ'and R in the motor circuit. This circuit includes as before,'the winding Gof the switch S, and this switch will immediately close its contact-s, but no resistance will be cut out until the operator again moves his switch to position 2. To stop the motor, the operators switch is moved to the central position as shown in the drawing, thereby opening the motor cir- .cuit. I

:If the operators switch is moved-to positions 3 and 4 the same operation will be obtained as that describedfor positions 1 and 2 except that the current is reversed in 30 the-motor armature thereby causing the motor to run in the opposite direction. :It will be noticed that the arrangement of the connections between the contacts and the windings of the switches S and S and between the winding of the switch C? and the operators switch permits the circuit through theswitch contacts to be opened to insert resistance while current. is still flowing in the motorcircuit without causing serious arcing at the switch-contacts. This is an advantage since it is unnecessaryto provide blow-out magnets and the necessary details for the contacts of'the resistance switches.

EInthe system shown in Fig. 2, an additional bank or resistance R is used. When the operators switch is moved to position 1, the: motor circuit is closed including the resistances It, R and R This circuit does not include the winding 0 of the switch and the switch S," therefore, does not close as long as the operators switch reroains in position 1. When the. operators switch. is-moved to position 2, the current then flows. through the resistance It and the winding .5 C in a branch parallel to the resistancelt and thence through the resistances .It ;'and R If the current in the inotor circuit exceeds a certain value the switch S" williremain open until the current has 1 0 diminisl'ied, whereupon it will close its con-v tacts .and the motor circuit will then includeithe winding G the contact switch S,

the windingO and the resistances R and B? to .the negative. The motor circuit through the contacts of the operators 7 switch can easily be traced. The closure of the switch S cutsout the resistances It, and

R in parallel and the switch S remains closed until the switch S closes. This will occur when the current in the motor circuit is reduced to a predetermined value. When the switch S closes, the resistance R will he cut out, the winding C-will be decnergized,-Yand the winding C energized. The

switch S opens and the switch S remains open until the motor current is diminished, whereupon it will close its contacts and cut out the resistance R The motor is now connected across'the line in a circuit including only the contacts and windings of the switches S and S When the operators switch is moved back to position 1, the circuit through the windings and contacts of the switches S and S is opened and the resistances R, R and R are inserted in the motor circuit causing the motor to run at a reduced speed. The switches do not open their contacts until after the circuit through them has been opened at the contacts of the operators switch, and no arcing at their contacts takes place.

On moving'the operators switch to posi tions 3 and4: the same operation will take place as that descr'bed for positions 1 and 2 except that the current through the motor armature is reversed, causing the motor to run in the opposite direction.

It will be obvious to those skilled in the art that numerous changes can be made in the apparatus without departing from the spirit of my invention.

I 1. In a current-varying controller, a controlled'circuit, a plurality of switches having contacts in the circuit, operating wind-- ings for the switches, means for connecting at-least two of the windings in the controlled circuit at thewill or the operator, means 'whereby the closure of the first switch energizes the winding of the second switch, and means controlled by the second switch for deenergizing the winding of the first switch.

2. In a current-Varying controller, a controlled circuit, resistances for the circuit, a series of switches for cutting out the resistances, operating windings therefor arranged to be connected in the controlled circuit, means for causing the first switch to open when the second switch closes, and a no contact in the circuit of the second switch winding closed at the will of theoperator.

8. In a motor-controlsystem, an electric motor, resistance for controlling the same,

a series of. switches having contacts for con-. trolling the resistance,

operating windings for the'switches arranged'to be connected in circuit with the motor, and means for connecting the motor in series with two parallelcircuits, one of the parallel circuitsgineluding the contacts of one or more'p t the switches, and the second including tlti' said resista e, the circuits being arranged, when the secon .switch of the series is closed, to cause the first switch of the series to open, 5 and means whereby the second parallel circuit is caused to be in circuit with the motor prior to'the opening (it the first parallel circuit.

4. The combination of resistance, switches 15% having operating windings contacts adapted to be conneceed is the motor 3lI'-= cuit, operators contacts for connecting the Winding of one switch in series with the resis'cance, operators contacts for connecting' the Winding of the next succeeding switch in series with she first Winding and in shuns with a part or" the resistance, but only after the contacts of the first switch have closed, the consacts of the second switch *vwflen closed being arranged. so out; out she first Winding and another portion of the resistance 5.. in a motor control system on electric motor, resistance for controlling the same a series of switches for combrolling the r sistance, operating windings therefor successively energized by current through the motor, means Wsereby the second switch in closing causes the first switch to open, and

means for remsertmg Joe resis I 7 v 11 r' n r, -mosor CITCUJL Woes bee see-one closed 6, in a motor control motor, resistance for so a series swi zches f0 sisszmce opera-fine w cessiveiy 2110 501, means closing causes the 3110s Signed Gleveianc of Sept, Wltnesses A, W. CLAEPERTON? M, Dismiss 

